Clamp



Oct. 22, 1935. H- W DENHARD 2,018,398

CLAMP Filed Jan. 4, 1935 umn/manual NVENTOR. HARRY W. DENHARD.

A TTORNEY Patented Oct. 22, 1935 UNITED STATES PATENT OFFICE CLAMP Application January 4, 1935, serial No. ssa i l 4 claims. (c1. 21o-2oz) This invention relates to a clamp for securing or anchoring the edges of a sheet of material, such as cloth, paper, woven wire or'sheet metal to a base member. More particularlyy the invention relates to a clamp for securing thefilter medium of a filter to its support, base or frame.

For the purposev of filtering sugar cane settlings resort has been made to a punched `sheet metal filtering screen or medium, but considerable difiiculty has been experienced in securing this type of filter medium to the cylindrical surface of a continuous sectionalized rotary drum filter. As is well known in the filtration art, the drum of a continuous rotary drum filter is divided into individual sections or compartments by spaced parallel division strips running longitudinally of the drum. To facilitate repair and inspection it is oftentimes desirable to cover each section or compartment with an individual panel of filter medium rather than to cover the drum with a single continuous sheet of filter medium. There isv always a certain amount of Amovement of the filter medium at the point at which it is attached to the division strip, and this movement tends, upon the continued use of a filter, to fracture and weaken the filter medium at this point. This provision of a mechanism by which the edges of the various panels of filter medium forming the 35` surface of a rotary drum filter may be detachably clamped'to their Arespective division strips without resorting to sharp bends in the filter medium itself. l More specifically the object of the invention is the provision of a base member having a channel therein formed with undercut walls and provided with a V-shaped clip and a wedge member for detachably locking adjacent panels of filter medium to the upper face of the channeled base member. l

The invention possesses other advantageous features, some of which with the foregoing, will be set forth at length in the following description where that form of the invention which has been selected for illustration in the drawing is out- Referring to the drawing: l'

Figure 1 is a cross section of a portion of the periphery of a rotary drum filter illustrating one form of the invention as applied to the ldivision strip of the filter. v 5

Figure 2,is an isometric view of one of the V- shaped clips used for holding the filter medium in place. L

Figure 3 is an exploded view of a division strip, the adjacent panels of lter medium, the V- 10 shaped lockingfstrip and the rod used for wedging the V-shaped clip in position.

Figure 4 is a cross section taken through a division strip withl the adjacent panels of'filter medium and V-shaped clips in position prior 15 to the insertion of the rod wedge member.

As shown in Figure 1 a division strip I is secured to a cylindrical shell 2 in, any'suitable manner, such as by riveting. Secured either directly to the shell ,2 or in the event that shallow comzo' partments aredesired, to a spacing member 3, is a vsupporting screen 4, provided with ribs 5, which serve to hold the filter medium 6 in spaced relation with respect to the supporting screen 4, to thereby form the filter section or compartment 25 'I. As is well known in the industry, communication is established between each of the filtercompartments and the filtrate valve by means 'of suitable filtrate pipes 8v secured to the filter drum byy means of a fitting 9. o

The division strip I is provided with lateral flanges II which overhang and rest on the edges of the supporting screen 4.

As best shown in Figures 3 and 4 the division strip Ivis provided with a longitudinally extended a5 channel I2 formed by the undercut lateral faces of the wallsv I 3 and I4. It should be noted that the angle formed by the upper face of the division strip I and the lateral undercutfaces of the channel I2 is less than 90. Adapted to strado dle each ofthe shoulders formed by the undercut lateral walls I3 and I4, and the vupper face of the division strip, are V-shaped clips I 5. vThese clips are formed by a horizontally extending leg I6 adapted to overlie the edge of the filter medium 6 5 and a depending leg I'I adapted to engage one of the lateral undercut walls or faces of the channel i I2.l The angle formed between the legs I6 and I'l of the clips should be somewhat smaller than the angle formed between the upper face of the 50 division strip I and the undercut lateral faces. Wings or lugs I8 are cut from the downwardly extending legs I'I of the strips I5, at spaced interivals along the length of the clip, and as clearly shown in Figures 2, 3 and 4 these lugs are bent 55 outwardly or away from the downwardly extending legs I1. As shown in Figure 1 the clips Il are held in their operative position by means of a rod I9 wedged in the channel I2 against the .opposed depending legs I1 and lugs `I8 of the clips I5. As can be'seen from an inspection oi Figure 1 the wedging action of the rod I8 has a tendency to rotate the outer ends of the horizontal legs of the' clips I 5 about the points at which the depending legs I1 of the clips contact the undercut lateral walls I3 and Il of the channel I 2,\thereby clamping the edges of the sections or panels of filter medium 6 against the upper face of the division strip I. The function of the lug I8 is to form a vertical extension of the apices of the clips against which the rod I9 may press if the center of the rod is forced beneath the apices of the slip.

The division strip I, the clip I5 and the rod I9 may conveniently be made of brass, and for certain classesV of Work the panels of iilter medium 8 arealso made of brass.,

It is to be noted that by means of the above construction the individual panelskof tllter medium may be lclamped to their division strips without the necessity of forming sharp bends in them as has been the practice in the pastand that as a consequence the minute fractures resulting from bending beyond the elastic limit are obviad. Furthermore, this construction provides a clamp with which the filter medium may be quickly attached or detached by the simple operation of inserting or removing the wedging rod.

I claim:

1. In a filter; a division strip provided with a shoulder having an undercut face; a sheet of iilter medium resting on the upper face of said shoulder; a V-shaped clip straddling said filter medium and undercut face and means for locking said clip in place.

2. In a lter; a division strip provided with a pair of spaced shoulders each having an undercut face and forming between them a channel ex- 5 tending longitudinally the length of the division strip; a sheet of nlter medium resting -on the upper face of each of said shoulders; V-shaped clips straddling said illter medium and the undercut faces of said shoulders and means disposed within l0 said'channel for locking said clips in place.

3. In a lter; a division strip provided in its upper face with a longitudinally extending channel having undercut lateral faces; two'sections of lter medium disposed over the upper face of l5 said division strip, one on each side of said channel; V-shaped clips engaging the sections of filter medium and said lateral undercut` faces, the angle formed between the legs of said clips being less than the angle formed between the upper and 20 lateral faces of the division Strip: and meansfor locking said clips in place.

4. In a illter; a division strip provided in its upper face with a longitudinally'extending chanl nel having undercut lateral faces; two sections 25 of filter medium disposed over the upper face of said division strip, one on each side of said chan. nel; V-shaped clips engaging the sections of iilter medium and said lateral undercut faces, the angle formed between the legs of said clips being less 30 than the langle formed between the upper and lateral faces of the division strip; outwardly bent 

